Originally posted by what?
as far as its function you must remember that this is not meant to be a stand alone gallery. it is merely a new wing for the gallery and a new face for the national gallery on nassau st. a primary reason for its construction was to (re)announce the galleries presence to the city. judging by the amount of people who were in it any time i was there it seems to definitely have increased the populaity of the gallery.
it does give over a lot of space to bookshop cafe etc. but these are valid parts of any modern gallery.